Estuarine Restoration in San Francisco Bay: Design and Adaptive Management

National Conference On Ecosystem Restoration

Baltimore, MarylandAugust 5, 2011

Eric Jolliffe, Bill Brostoff, and Fari TabatabaiPresented by Pete LaCivitaU. S. Army Corps of EngineersSan Francisco District

OverviewSonoma Baylands Monitoring

Hamilton Wetlands Restoration Project Construction

Napa River Salt Marsh Restoration Design

South San Francisco Shoreline Study

Many other non-Corps restoration projects in the SF Bay area

Planning

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Northern San Francisco Bay

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Southern San Francisco Bay

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Hamilton

Sonoma Baylands Napa

Shoreline

Sonoma BaylandsBackground

• Site diked for agriculture and subsided ~ 6 ft

• Goal: establish a tidal wetland• 2.1 mcy of dredged material

placed to 0.5 ft below marsh plain

• Levee breached in 1996• Sponsor: California State

Coastal Conservancy• Partners: Sonoma Land Trust

and Port of Oakland 6

Sonoma BaylandsMonitoring & Adaptive Management

• Physical: dredged material fill elevations, chemical constituents, channel morphology, tidal regime, peninsula crest elevations, tidal sedimentation, and water quality

• Biological: Vegetation, birds, fishes, endangered species, and benthic macroinvertebrates

• Monitoring (O&M funds & the local sponsor) will continue until success criteria are met

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Sonoma BaylandsMonitoring & Adaptive Management

• Monitoring Results– Establishment of tidal connection and

vegetation slower than expected– Slow development on predicted trajectory– Planned management intervention to increase

tidal connection not needed• Status

– Vegetation representative of SF Bay establishing (Spartina foliosa,Salicornia virginica)

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Hamilton Wetlands Restoration Project Background

• Site originally wetland/intertidal salt marsh• Diked and drained mid- 19th century• Converted to Army Air Base in 1932• BRAC in 1980’s• Project intent

– “ecosystem restoration” – dredged material placement≈ 630 ac of wetland≈1000 ac total project

• Sponsor: California State Coastal Conservancy

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Hamilton Wetlands Restoration Project Goals

• Restoration goals developed by sponsor & stakeholders– Diverse array of wetlands and

habitat types– Replace habitat/function of

disused agricultural fields for shorebirds

– Sustainability • Minimal site maintenance• Habitat independent of sea-level rise

– Biodiversity, wildlife, TES• Placement for dredged material

- Benificial use (LTMS)10

Three broad habitat types:• Intertidal marsh and mudflat• “Seasonal” wetland• Upland

Hamilton Wetlands Restoration ProjectGoals

o Seasonal Wetland

o Tidal Wetland

o Wildlife Corridor

o Tidal Pan Berms

o Intertidal Berms

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Hamilton Wetlands Restoration ProjectStatus

• Dredged material placement complete (6 mcy)• Tidal portion: Elevations raised to 4.5 ft (1.5 ft below marsh plain elevation) -- natural sedimentation will bring site grades to marsh plain elevation• Seasonal wetland: Being dried and contoured• Native plant nursery being built on site• Levee to be breached in Fall 2012• USACE will monitor for 13 years, then local sponsor assumes responsibility

Hamilton Wetlands Restoration Project Adaptive Management

• Different approaches for each habitat type– Certainty of outcome– Availability of BMPs

• Uplands – Low levels of uncertainty associated with creating

upland habitat– Existing tools for improving upland habitat quality are

well developed and readily implemented– Monitoring emphasis on founder plantings and

invasive plant control efforts

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Hamilton Wetlands Restoration Project Adaptive Management

• Tidal Wetlands– Available reference sites and restoration

successes– Monitoring will compare results to reference sites– Specialized monitoring will be developed in

response to any uncertainties as needed– Basic monitoring for

• Basic coastal salt marsh function• Birds: winter use be similar to reference sites• Fish: ‘general suitability”• Endangered spp.: presence & extent habitat• Benthic inverts: “appropriate” colonization

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Hamilton Wetlands Restoration Project Adaptive Management

• Seasonal Wetlands– Original concept: unvegetated areas with ponds

ranging from brackish to near freshwater– Do not exist in nature– High levels of uncertainty

• Engineering underpinnings may not work• Invasive spp.• Predators• Response to sea level rise• Reference sites rare, poorly understood• Restoration successes very limited

– Science-driven approach -- testing hypotheses in the monitoring plan

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Hamilton Wetland Restoration Project What’s Next?

• Bel Marin Keys (adjacent) 1600 acres• Restoration plan is under development.• Funding issues

– particularly long-distance transportation of dredged material- Aquatic Transfer Facility vs. unloader & scow- WRDA changes cost sharing ratio

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Napa River Salt Marsh RestorationBackground

• Site diked (9,500ac), used for agriculture, and later salt ponds (7,200 ac)

• Current problems include water quality and deterioration of levees

• Goals– Restore habitat for terrestrial and

aquatic species of concern– Manage ponds for resident and

migratory shorebirds & waterfowl– Improve water quality

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Napa River Salt Marsh RestorationMonitoring and Adaptive Management

• Monitoring: water quality, sedimentation, THg and MeHg, pelagic and benthic inverts, algal productivity, plants, and fishes

• Adaptive management: Possible conversion of ponds to tidal marsh

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Napa River Salt Marsh RestorationStatus

• In cooperation with related efforts (Cal DFG)– Restored 7 southern ponds

in 1995 - 2006• USACE

– Final design stage -preparing construction plans for northern ponds

– Levee maintenance, salinity reduction, replacement of water intake structures, habitat restoration 19

South San Francisco Shoreline StudyBackground

• Examining restoration and Flood Risk Management opportunities

• Coordinating with “South Bay Salt Pond Restoration Project”

• Sponsor: California Coastal Conservancy

• 25 sq mi dominated by former salt ponds

• Goal: 15,100 acres of various kinds of coastal wetland habitats (total study area = 25 sq mi)

• Largest wetland restoration project on the west coast of the U.S.

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South San Francisco Shoreline Study Opportunities

• Planning centered around establishing geomorphic features not being created by natural processes (e.g., high marsh and upland)– Strategy for breaching levees (e.g., where,

number?)– Lowering outboard levees (where, how far?)– Creating marsh, transitional, and upland

habitats (proportions, dredged material use?)21

South San Francisco Shoreline Study

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South San Francisco Shoreline Study Status

• Feasibility phase• Funding uncertainties• Sponsors: California Coastal Conservancy,

Santa Clara Valley Water District• Partners: US Fish and Wildlife, California

Department of Fish and Game

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Conclusion & Reflections

• Subsided land suggests dredged material placement – USACE involvement

• Protracted monitoring for HWRP & Sonoma Baylands

• Many potential restoration sites, scenarios, in SF Bay Estuary– USACE involved with large projects, majority

of area• Sea level rise presents a challenge –

limited areas for wetlands to move up 24